In case you haven’t heard, the next book in Rebecca Yarros’ Empyrean series, Threshing Day, is coming out this month! 

Considered book 3.5 in the series, which began with Fourth Wing, this companion book features thirteen stories following the books’ characters and their dragons. 

With the series’ previous book, Onyx Storm, having been published in January 2025, we don’t blame you if you need a quick recap on the series’ dragons and their roles. 

Read on for a quick overview of how dragons function in Fourth Wing and the rest of the series, then deep-dive into the different dragon colours and revisit some of the most prominent dragon characters from the books. 

🚨 SPOILER WARNING: Spoilers ahead in relation to Fourth Wing, Iron Flame and Onyx Storm. Some details below may allow readers to infer details from these books. 🚨

About dragons in the Empyrean series 

In the Empyrean series, dragons function as magical companions of their human riders. But why – you might be wondering – do dragons even need this human alliance in the first place?

Throughout the books, the human-dragon partnership is symbiotic, with both species keeping the other safe. 

The primary goal of dragons in the series is to keep their hatching ground, The Vale, safe. While the dragons can generate magic to power wardstones which fight off more nefarious forms of magic (like venin), they alone cannot weave magical wards to block it. Thus, they need the humans’ technical prowess and dexterity to help complete their proactive defences. 

From the human perspective, the people of Navarre also want to protect their territory. Using the dragons’ magic,  humans can weave protective wards and runes to keep the enemy out. 

Their role

In addition to generating the magic that powers the wardstones – and thus, the weaves – dragons also act as companions to humans in the series. 

Acting as part-family, part-weapon, the dragons are both tools and relatives to the riders who they bond with. Unlike other fantasy series, the dragons of Fourth Wing and the other Empyrean books are more than mere pets. 

Because they consider themselves superior to humans, dragons take great care (and pride) in their bonded riders and have more agency in deciding who to channel their powers to. 

In addition to generating power for humans to use, the dragons in Yarros’ books operate as transportation and weaponry, allowing their riders to travel great distances and battle enemies. 

Dragon archetype

While the dragons of the Empyrean series are unique in how they’re portrayed, they draw most closely on the archetypes of Medieval European dragon representations. 

With four legs and two wings, they resemble other Western dragon depictions, like those written about by J.R.R. Tolkien and Ursula Le Guin. 

While there are wyverns in the Empyrean books, Yarros explicitly distinguishes them from dragons by the fact that they only have two hind legs – mirroring George R.R. Martin’s wyverns from the Game of Thrones books. 

In contrast to this Western archetype, Eastern dragons are usually portrayed as more serpent-shaped and wingless, mastering the elements of air and water rather than fire or earth. 

Abilities 

As introduced in Fourth Wing, dragons are much more than docile pets. As independent creatures themselves, dragons have countless abilities – some of which can be magnified by their human companions: 

• Flight 
• Combat 
• Channeling magic
• Elemental magic 

Dragon colours 

In the Empyrean series, dragon colour is closely tied to rank, with each colour signifying different dens. (Think: more like family lines or Hogwarts houses than hair colours.)

Each colour is inherited from the dragon’s lineage, with different dens possessing different qualities. 

• Black: Descendants of the Dubhmadinn line, rarest colour, intelligent and cunning
• Blue: Descendants of the Gormfaileas line, ruthless and intimidating, typically larger than other colours
• Red: Unknown lineage, most violent colour, prefer to be approached from the left and the front, short-tempered 
• Orange: Descendants from the Fhaicorain line, most unpredictable colour, temperamental
• Green: Descendants of the Uaineloidsig line and Cruaidhuaine line, particularly intellectual, rational
•  Brown: Unknown lineage, loyal 
• Irid (iridescent): Unknown lineage (but shared by Andarna and Leothan), shiny, reflective scales, unique ability to break magical bonds, only colour which can create a second bond with a paired human, pacifists 

Dragon tail types

Throughout the series, dragon breeds are signified by tail type, with each tail acting as a different weapon and signifying their preferred fighting style. 

All dragons are born with a feathertail, then evolve a specific tail type depending on their needs. 

• Feathertail: Tail ends in a feather, juvenile dragon
• Clubtail: Tail ends with a club
• Daggertail: Tail ends with knife spikes
• Morningstartail: Tail ends with a spike-covered club, making this one of the most deadly breeds
• Scorpiontail: Tail ends with poison barbs
• Swordtail: Tail ends long and sharp, like a sword 

Dragon characters

Because each rider has a dragon counterpart, the dragon characters in the Empyrean series are equally as important as the human characters. 

Here are a few of the most prominent dragon characters from Fourth Wing, Iron Flame and Onyx Storm: 

Tairneanach (AKA Tairn)

• Colour: Black
• Breed: Morningstar tail 
• Rider: Violet Sorrengail 
• Details: The most-celebrated and second-largest dragon in active service, chose Violet because she protected Andarna, mated to Sgaeyl 

Andarnaurram (AKA Andarna)

• Colour: Gold → irid
• Breed: Feathertail → morningstartail
• Rider: Violet Sorrengail
• Details: Originally bonded with Violet as a juvenile, evolves into an irid morningstartail in Onyx Storm, grants Violet a dangerous second signet, which she must keep secret

Baide

• Colour: Orange
• Breed: Scorpiontail
• Rider: Jack Barlowe
• Details: Aggressive like her rider, eventually betrayed by him, breaking a previously held belief that a human could not harm their dragon

Cath

• Colour: Red
• Breed: Swordtail
• Rider: Dain Aetos
• Details: Strong-tempered and powerful, allows Dain to channel the ability to read memories 

Codagh

• Colour: Black
• Breed: Swordtail
• Rider: General Melgren
• Details: The largest and oldest dragon, highest on the hierarchy

Leothan

• Colour: Irid
• Breed: Feathertail
• Rider: None
• Details: Tells Andarna about her heritage, convincing her to break her bond with Violet and accompany him to defend Navarre, can mind-speak with humans who aren’t bonded to him

Marbh

• Colour: Orange
• Breed: Daggertail
• Rider: Brennan Sorrengail
• Details: First believed to be dead, allows Brennan the rare ability to mend/heal 

Sgaeyl

• Colour: Blue
• Breed: Daggertail
• Rider: Xaden Riorson
• Details: Previously bonded to Xaden’s grandfather – causing Xaden to develop a second signet, vicious temper and aloof nature, mated to Tairn

Gaelic dragon names in the Empyrean Series

One interesting aspect of the Empyrean Series lies in author Rebecca Yarros’ naming conventions. Throughout the series, dragons are given gaelic names, often foreshadowing different aspects of their character or storyline. 

The table below shows some dragon names from the series, their association with Scottish Gaelic and translations. 

Dragon name	Association with Scottish Gaelic	Meaning
Tairneanach	Scottish Gaelic word	Thunder
Andarnaurram	A portmanteau of three Scottish Gaelic words: an dàrna urram	The second honour
Baide	Similar to the word ‘baid’	Group/heard
Cath	Scottish Gaelic word	Battle
Codagh	Similar to the word ‘cogadh’	War
Leothan	Similar to the word ‘leathann’	Broad/wide
Marbh	Scottish Gaelic word	Dead
Sgaeyl	Similar to the word sgáil	Shadow

Coming out September 2026

Previous books in the series